Aluminum alloy



I Patented Apr. 18, 1933 I sonar 0. mos, or

m ao'ax. n. 1.,

amnnmnr ALLOY Ho Drawing.

My invention relates to a series of aluminum alloys of novel compositionand properties. The alloys of my invention are particularlycharacterized by the presence of boron and magnesium.

' Alloys consisting principally of aluminum and containing .substantialamounts of boron and magnesium are characterized by being both lighterand harder than aluminum. The amount of magnesium in the new alloys mayT vary from about 0.25% to about 2.25%, the preferred amount bein fromabout 0.75% to 1.5%, and the boron mm 0.05% to 2%, although at least0.25% is preferable and in many cases it is preferable not to add over0.75% of boron due to the increased brittle ness caused byhigheramounts. A particu lar composition havingvaluable properties ismagnesium 1%, boron 0.5%, and the' remainder aluminum.

While the alloys consisting substantially solely of aluminum, magnesiumand boron are valuable. for many uses, the alloys are Vanadium -aparticularly valuable when they also contain other metals. Alloys ofaluminum, mag- I 'nesium andboron, containing such metals as vanadium,tungsten, molybdenum, chromium, cobalt, copper and zinc, provide aseries of alloys characterized by their light weight, together with 'ahigh hardness and tensile'strength. In neral, the new alloys also havesurprisingly high electrical conductivity and resistance to corrosion.

The following specific formula; are illustrative of the wide range ofcompositions of the invention:

A particularly valuable alloy embodying 40 my invention has thefollowing composition:

Magnesium 1.25% Boron y 0.75% Vanadium 0.75% Tungsten 0.75%"

Aluminum remainder Application am June so, ma. sci-m Io. mazes.

Another very valuable alloy having high tensile strength and electricalconductivity and characterized'byits. malleability, noncorrosiveness andgood casting properties is:

Magnesium 1.50% Boron 0.50% Vanadium 0.50% I Coba v 0.75% Aluminumremainder copper containing alloy of high tensile strength is obtainedfrom the following composition: u Magnesium 1.00% Boron r 0.7 5% Copper3.75% Aluminum remainder A strong and readily orkable alloy isrepresented by the following composition:

Magnesium 1.00% Boron 0.50%

0.50% Copper 3.00% Aluminum remainder An alloy of valuable roperties,includmg a high degree of bar ness, has the following compositionMagnesium 1.00% Boron 0.50% Vanadium, 0.50% Zinc. 1.25% Aluminumremainder In general it is advantageous to use metals other thanaluminum, magnesium and boron, in amounts of from 0.25% to- 5%. Theamounts added will, of course, vary with the nature of the added metalsand with the number of alloying metals used.

In neral 1t may be said that a principal funct on of boron in the alloysof the invention is to increase the hardness, and a principal functionof the magnesium is to decrease the specific gravity and increase the vresistance of the alloys against corrosion.

' As indicated above, other metals may be added for the purpose ofincreasing tensile strength, malleability, resistance to corrosion,electrical conductivity and other special roperties.

loys of the invention as described above have been obtained having aspecific gravity of 2.66 to 2.70; a tensile strength when cast of 30,000to 41,000 pounds per square inch, and when mechanically worked of from51,000 to 56,000 pounds; and an electrical conductivity of 50-58(Ag=100).

The metals may be utillzed either in the cast condition, or they may berolled, drawn or otherwise worked. Mechanical working is preferablycarried out at a temperature of 150450 C. and such working eflects amaterial increase in the tensile strength of the alloys. WVire drawnfrom the alloys of the invention is particularly valuable, since itcombines a relatively hlgh tensile strength with a relatively highconductivity. A further valuable property of such Wires is that sleetand snow do not readily stick to them.

Anadvantageous method of producing the alloys of the invention is asfollows: The aluminum is melted in a crucible and covered with a layerof powdered charcoal. The charcoal serves to protect the metal fromoxidation and to reduce these metals which are added in the formofoxides. The magnesium is added as metal and the boron as oxide. Othermetals may be ,added as such, or in the form of their oxides, accordingto the nature of the particular metal. The added metals or their oxidesare advantageously added enclosed in aluminum capsules. The boron oxideis preferabl added first,although it may be added together with themagnesium. The other metal oxides may be added together. I

This application contains subject matter in common with my applicationSerial No. 612,651, filed May 20, 1932.

I claim: I

1. Alloys consisting principally of aluminum and -characterized bycontaining from 0.05 to 2% of boron and from 0.25 to 2.25% of magnesium.

2. Alloys consisting principally of aluminum and characterized bycontaining from 0.25 to 0.75% of boron and from 0.75 to 1.5% ofmagnesium.

' In testimony whereof, I affix my signature.

COURT C. TITUS;

